To improve low-temperature impact resistance of molded articles made from thermoplastic resins, various elastomers (rubber components) are blended with or plasticizers are added to the thermoplastic resins. Alternatively, both elastomers and plasticizers are added to the thermoplastic resins. When costs are no object, thermoplastic elastomers are used in some cases.
For example, Japanese Examined Patent Application Publication No. 06-45748 discloses a polyamide composition which includes a polyamide, a graft modified ran-copoly(ethylene/α-olefin) and a low molecular weight modified ethylenic random copolymer added to the polyamide in order to improve its low-temperature impact resistance. The graft-modified ran-copoly(ethylene/α-olefin) herein is graft-modified with an α,β-unsaturated carboxylic acid or its acid derivative, and the low molecular weight modified ethylenic random copolymer is a low molecular weight ethylenic copolymer graft-polymerized with an α,β-unsaturated carboxylic acid or its derivative. Japanese Unexamined Patent Application Publications No. 60-156747 and No. 01-272659 disclose resin compositions having improved impact resistance and comprising a polyester and a graft-modified polyolefin.